Children exposed to fluoridated water before the age of ten have a higher risk of a number of serious neurodevelopmental issues, a new study suggests.
The paper, published in BMC Pediatrics, shows that autism-spectrum disorder, attention-deficit/hyperactivity disorder, intellectual disability and other delays in development were all visible at higher rates among children exposed to fluoridated water before their tenth birthday.
The researchers behind the study, David and Mark Geier, are warning that the risks of water fluoridation must be carefully reassessed.
They analyzed data from the Independent Healthcare Research Database, taken from de-identified healthcare records from the Florida Medicaid System during the period 1990-2012.
Since some counties in Florida have municipal fluoridation and others don’t, they were able to compare the health of children exposed to water fluoridation for their whole lives—over 25,000 children—with the health of around 2,500 children who weren’t.
The researchers examined fluoride exposure and health outcomes during the first year and the first ten years of life.
The results showed that in the first year of life, there was a statistically significant decrease in the risk of tooth decay with exposure to fluoridated water, as well as a statistically significant increase in the risk of neurodevelopmental disorders.
The ten-year results were much more striking. After ten years of fluoride exposure, the risk of tooth decay was nearly four times lower in exposed children, but the children had a significantly higher risk of developmental disorders—nearly seven times greater for autism and two times greater for intellectual disability, most notably.
At the beginning of November, Robert F. Kennedy Jr. made clear that removing fluoride from public water will be one of the new Trump administration’s top health priorities.
“On January 20, the Trump White House will advise all U.S. water systems to remove fluoride from public water,” Kennedy Tweeted.
“Fluoride is an industrial waste associated with arthritis, bone fractures, bone cancer, IQ loss, neurodevelopmental disorders, and thyroid disease. President @realDonaldTrump and First Lady @MELANIATRUMP want to Make America Healthy Again.”
Two months earlier, in a landmark ruling, California-judge Edward Chen ruled that the dangers of water fluoridation needed to be addressed. Chen ruled that the EPA must ensure there is a sufficient margin between the hazard level for fluoride and the exposure level.
“If there is an insufficient margin, then the chemical poses a risk,” the judge wrote.
“Simply put, the risk to health at exposure levels in United States drinking water is sufficiently high to trigger regulatory response by the EPA.”
Judge Chen also cited “scientific literature in the record” that “provides a high level of certainty that a hazard is present” and demonstrates “fluoride is associated with reduced IQ.”
Judge Chen’s order comes weeks after the National Toxicology Program found a link between levels of fluoride of exposure and a reduced IQ in children. The Program found that exposing children to higher levels of fluoride, at around 1.5 milligrams per liter, is “consistently associated” with lower IQ in children.
A number of municipalities have since voted to end public fluoridation, and at the end of February Utah became the first state to ban it.